Server Settings Explanation

[Lord Shadow]

Did anyone find or make guide explaining server settings in detail? Some settings are very clear but others... well I would like to not go through trial and error to understand them.
Example be:

Friendly Fire Damage Switch
Friendly Fire Damage Switch Between Players

Does it mean NPCs can hit be, do I need to have both on to allow other players to hit one another?
Also is it possible to keep all your stuff after death when you spawn on you?

So bottom line is some server settings are not clear what they do by its name itself.